The present invention relates to a method of mass spectrometry and a mass spectrometer.
It is known to separate ions according to their ion mobility in an ion mobility spectrometer.
A mass filter may be provided upstream of an on mobility spectrometer and may be set to transmit only ions having a certain mass to charge ratio. In some circumstances two ions having slightly different ion mobilities can be partially resolved by the ion mobility spectrometer suggesting that the ions comprise two isomers having, different conformations and with the difference in ion mobility being due to the different conformations. However, conventional ion mobility separation techniques provide limited information about the different conformations and it may be desired to have both a greater degree of understanding concerning the nature of the two different conformations and also a greater degree of confidence that the observed ion peaks in an ion chromatogram do in fact represent ions having different conformations.
In other circumstances the ion mobility spectrometer may be unable to resolve ions having different conformations so that a single ion peak is observed in a resulting ion chromatogram. However, it may be desired to see whether a single ion peak in an ion chromatogram actually comprises two (or more) isomers having different conformations.
Conventional ion mobility spectrometry techniques provide only a limited amount of information and a limited degree of certainty when seeking to analyse isomeric ions.
It is desired to provide an improved method of mass spectrometry and mass spectrometer.